Rafa vs. Roger in Sony Ericsson semifinal

It may not be occurring at the usual stage of a Grand Slam tournament or for the same monumental stakes, but the Rafa-Roger rivalry will make its first appearance on U.S. soil in six years Friday night at the Sony Ericsson Open.

And they got to their 23rd meeting in this marquee blockbuster semifinal between No. 1 vs. No. 3, literally by a neck. Make that two necks.

First, injury-prone Frenchman Gilles Simon bid adieu after just 10 minutes and three games with a sore neck in his Thursday afternoon quarterfinal against third-ranked Roger Federer.

Then in the evening session, world No. 1 Rafael Nadal seemed to be holding up his end of the bargain until he, too, received on-court treatment for a stinger up his right arm, shoulder and neck before fending off last year's runner-up Tomas Berdych, 6-2, 3-6, 6-3 in a 2:17 thriller.

"I hope it's nothing important," Nadal said of the injury.

"Everybody looks at it like a rivalry, but for me it's always special when we play each other. We are very close. I don't know if the rest of the rivalries in the history of tennis played as many matches as we have."

Despite the blazing 22-0 start by No. 2 Novak Djokovic, deep down Federer - who is 22-3 this year with all three losses to Djokovic - knows his one true rival is a certain hyper Spaniard with a headband.

"My No. 1 rival to me it seems is Rafa," said Federer, who has been on court for just 3:48 in four matches to Nadal's 6:21.

"It doesn't matter how many times I'm going to play all the other guys. We have that history and nobody can take it away from us. ... We've been in so many finals against each other and were able to play over four to five tough sets and have always shown a lot of respect toward each other. Those are the matches I'm really looking forward to.

"If you win, great; if you lose, that's OK, too, as long as you tried everything and learned something else from that match. But I am planning to win and that's why I have to be well prepared."

The disappointed gallery jeered a dejected Simon off the court.

"The sadness on the court is me," said Simon, who first felt the neck pain while hitting a backhand in an early-afternoon warmup. "Everybody's not happy about the match. Even Roger. … He prefers to win it with all the winners he can do." SImon was 2-1 against Federer, including a five-set loss in this year's Australian Open.

The early retirement brought back vivid memories of Goran Ivanisevic pulling out of the 1996 final on Key Biscayne with a sore neck after the same 10 minutes and three games, thus handing the title to Andre Agassi.

After seven straight letdowns of a Rafa-Roger showdown in America that was one match away from happening, Nadal saved three break points in the first game of the third set with three consecutive aces. He then achieved the critical break at 3-4 of the third set when a Berdych backhand clipped the net twice before dribbling back on his court.

"You can expect three aces from Andy Roddick, Ivo Karlovic, but from Rafa," said the seventh-seeded Berdych, whose 34th and final error floated over the baseline to seal his ninth straight loss to Nadal. "In the end it's just a little bit of bad luck."

The rivalry began in Miami in 2004 when a muscular, 17-year-old with wicked topspin strokes stunned the recently annointed No. 1 Federer in the third round.

Federer, 29, got revenge a year later in their second meeting in a five-set Key Biscayne final. But since, the tide has turned with Nadal, 24, owning a 14-8 edge over Federer, including 12-6 in finals and 6-2 in Grand Slams.

"When I became the world No. 1, I didn't really have that rival and I was very happy about it … being able to win, win, win and dominate," said Federer, who leads his friendly nemesis 4-3 on hard courts, but has a record 16 Slams to Nadal's nine.

"Later on I was able to say this is actually quite cool. Sleeveless, pirate pants, you name it, long hair, spins, [me with] more flat shots, double-handed against one-handed, lefty against righty. It all made sense and I was able to embrace it then."

In the overshadowed undercard afternoon semi, Djokovic takes on American hope Mardy Fish, who is 0-5 against the soaring Serb, but brimming with confidence after back-to-back triumphs over Juan Martin del Potro and David Ferrer.

"He has zero weaknesses right now," said Fish, who with a win will crack the Top 10 at No. 10 for the first time in his career. "Obviously, confidence is a huge part of our sport and he's got all of it right now."

ATP media relations guru Greg Sharko, said that this is the first time in tournament history that the top three ranked players in the world have reached the semifinals.